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31.
The carotenoid composition of cysts of seven species of fairy shrimps (Anostraca) was studied using high-performance liquid chromatography. Canthaxanthin was detected as the major pigment, but an important and often predominant fraction of it occurred in the cis-configuration, which is consistent with previous findings in Artemia cysts. Cis-canthaxanthin rapidly disappeared in nauplii of Thamnocephalus platyurus through conversion to all-trans-canthaxanthin and was preferably localized in the abdominal section carrying the genital segment of females, unlike in mature male animals. In contrast, the intense orange-red colour of the thoracopods and the cercopods in both sexes was only due to all-trans-canthaxanthin.  相似文献   
32.
Epizootic algae and Protozoa occur on the exoskeleton of fresh water branchiopods in temporary ponds in Morocco. Algal colonization seemed linked with turbid waters and access by the epibionts to the nutritive and oxygenated flows created by the rhythmical beat of the thoracic legs of the branchiopods. It also seemed linked to the mode of life (planktonic or benthic) of the host, and to their exposition to light. Appendages of anostracans, which swim ventral side up, bear a rich community of Chlorophytes, while in conchostracans, where body and appendages are protected by a bivalve carapace, and which swim ventral side down, epibionts colonize the valves, particularly near the hinge and umbo. The lack of algae on notostracans may result from their habit of living in the deeper part of ponds. Protozoans fixed on notostracan shields and on conchostracan valves or appendages, seem to benefit principally from the flow of nutrient- and oxygen-rich water created by the host.  相似文献   
33.
Somatic growth in S. proboscideus, fed Chlorella vulgaris increased with temperature reaching a plateau after about 8 to 11 days at between 26 and 31 °C. Survival was best below 29 °C. Fertility (the number of cysts produced per female) and survival, tested at 27 °C, demonstrated some variability as a function of the composition of four different diets. However, large variances and few replicates make exact evaluation impossible.It was found that S. proboscideus can successfully be cultured, using a variety of food sources. Only pure Spirulina platensis gave unsatisfactory results in terms of low cyst production and high mortality. Filamentous blue-green algae, because of their possible toxicity, should preferably be excluded from formulated diets.  相似文献   
34.
Four branchiopod species occur on the Maltese Islands, viz. Branchipus schaefferi, B. visnyai, Cyzicus tetracerus and Triops cancriformis. All four live in freshwater pools, but it is noteworthy that, beside B. schaefferi, T. cancriformis was recorded from a mesohaline, coast-fringing habitat.  相似文献   
35.
The known range of S. torvicornis is extended to areas of the Western and Central Sahara and Sahel. Morphological variation between populations is important, and cannot be accomodated within the known Iberian and Maghrebian subspecific taxa, which appear untenable. A grouping of populations according to drainage basins appears, however, possible. Populations of the Hoggar, Air, and Tibesti waters, draining towards the Soudanian zone, are more closely related than populations from waters draining towards the Atlantic. Tassili-n-ajjer populations from Central Algeria have individual characteristics, and deserve further study.  相似文献   
36.
Affordable biological technology for the reclamation of wastes and water of the waste streams from intensive livestock units is important in a country short of water. This study tested the concept of reclamation of waste by Streptocephalus macrourus (Crustacea: Anostraca) from the effluent of a high rate algal pond processing livestock wastes. S. macrourus showed a growth efficiency of 39% to 74% when fed optimal rations and cultured at densities between 10 and 400 1–1. The maximum daily growth rates (0.15–0.21) approximate the growth rates of cladoceran or rotifer cultures managed for maximal biomass production. S. macrourus' ability to withstand crowding enabled the production from S. macrourus cultures (up to 91.8 mg dry mass l–1 d–1, or 1241 mg wet mass l–1 d–1) to exceed production recorded from cladoceran or rotifer cultures. Temperature influenced growth rate, with the highest growth rate occurring at 24 °C. The dilution rate of continuously fed cultures influenced growth rate, with the optimum dilution rate tested being 10 ml organism –1 d–1. Mass mortality occurred when organisms were held at a density of 4000 l–1. S. macrourus is able to convert algae grown on livestock waste efficiently into anostracan biomass, and is able to give a very high daily production.  相似文献   
37.
During these investigations the following species of Anostraca have been found: Chirocephalus diaphanus Prevost 1803, Chirocephalus brevipalpis (Orghidan, 1953), Streptocephalus torvicornis Waga 1892, Branchipus serbicus Marinek & Petrov 1988, Branchipus stagnalis L. (1758) and Branchipus sp. Thus, the total number of species discovered in Yugoslavia is 13.The shape of the frontal shield and the degree of flexure of the distal articles of antennae II in males are of no relevance to taxonomy in the genus Branchipus Schaeffer 1776. However, the apophyses on antennae II in males, shape of antennae II and of the ovisac in females, structure of eggs, and of appendages appear species-specific. We conclude that the differentiation of B. stagnalis into two forms (forma typica and forma visnyai) as well as the separation of B. visnyai Kertész 1956 as a distinct species are unfounded.  相似文献   
38.
Graziella Mura 《Hydrobiologia》1986,134(3):273-286
The screening of the egg shell morphology of all italian species of Anostracans (14) by means of SEM, as well as the analysis of preliminary data on electrophoretical patterns of the adults, concerning the genus Chirocephalus (five species), suggest the need for a reconsideration, from a taxonomical point of view, especially as far as the species of the diaphanus group (Ch. diaphanus, Ch. ruffoi, Ch. salinus, Ch. sibyllae) are concerned.In this light, within the above mentioned group remarkable differences have been observed for Ch. ruffoi, whilst for other species like Ch. diaphanus and Ch. sibyllae, conspecificity is suspected. Electrophoretical and reproductive isolation studies, in progress, will provide a clearer understanding of the actual situation.Research carried out with M.P.I. (60%) and C.N.R. (chBr. 83.02549.04 Gruppo di Biologia Naturalistica) financial support.Research carried out with M.P.I. (60%) and C.N.R. (chBr. 83.02549.04 Gruppo di Biologia Naturalistica) financial support.  相似文献   
39.
A contribution to the knowledge of the anostracan fauna of Iran   总被引:1,自引:1,他引:0  
Mura  G.  Azari Takami  G. 《Hydrobiologia》2000,441(1):117-121
We report the finding of three anostracan species, Chirocephalus skorikowi Daday, 1913, Branchinecta orientalis Sars, 1901 and Branchinella spinosa. Milne-Edwards, 1840 in different localities in northwestern Iran. C. skorikowi was recorded in a lake at an elevation of 2400 m, whereas B. orientalis was found in a pond at 1280 m a.s.l. Co-existing B. spinosa and B. orientalis were collected in a pool close to the town of Tabriz, formerly indicated by Brehm (1954) as Estakr Chah, presently named EalGoli. Unlike Brehm (1954), we did not find Streptocephalus in the area of Tabriz.  相似文献   
40.
Supplement to " checklist="" of="" the="" anostraca""="   总被引:3,自引:3,他引:0  
Belk  Denton  Brtek  Ján 《Hydrobiologia》1997,359(1-3):243-245
Our 1995 "Checklist of the Anostraca" covered all species described through 31 December 1993 along with those described in the volume from the Second International Large Branchiopod Symposium (Hydrobiologia 298). This supplement includes new species (14) described through 31 December 1996, one change in rank and one new species discussed in this symposium volume, anew synonym, and correction of errors discovered in the original. We do not update new range extensions. With these additions and changes, we number the named anostracan fauna of the world at 273 species and six subspecies organized in 23 genera. The need for more study of anostracan zoogeography is again demonstrated by the fact that seven of the 16 species added to the checklist are know only from their type localities. Until we have more complete information on the distributions of the species, it will not be possible to make an accurate evaluation of the status of anostracan biodiversity. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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